com.hazelcast.map.impl.iterator

Class AbstractMapQueryPartitionIterator<K,V,R>

java.lang.Object

com.hazelcast.map.impl.iterator.AbstractMapQueryPartitionIterator<K,V,R>

Type Parameters:

K - the key type

V - the value type

R - in the case query is null, this is Map.Entry<K,V>, otherwise it is the return type of the projection

All Implemented Interfaces:

Iterator<R>

Direct Known Subclasses:

MapQueryPartitionIterator

public abstract class AbstractMapQueryPartitionIterator<K,V,R>
extends Object
implements Iterator<R>

Base class for iterating a partition with a Predicate and a Projection. When iterating you can control:

• the fetch size
• whether a projection was applied to the entries
• whether a predicate was applied to the entries

Field Summary

Fields

Modifier and Type	Field and Description
protected int	currentIndex
protected int	fetchSize
protected int	index
protected int	lastTableIndex The table is segment table of hash map, which is an array that stores the actual records.
protected IMap<K,V>	map
protected int	partitionId
protected Query	query
protected List<Data>	segment

Constructor Summary

Constructors

Constructor and Description
AbstractMapQueryPartitionIterator(IMap<K,V> map, int fetchSize, int partitionId, Predicate<K,V> predicate, Projection<Map.Entry<K,V>,R> projection)

Method Summary

Modifier and Type	Method and Description
protected boolean	advance()
protected abstract List<Data>	fetch()
protected abstract SerializationService	getSerializationService()
boolean	hasNext()
R	next()
void	remove()
protected void	setLastTableIndex(List<Data> segment, int lastTableIndex)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Iterator

forEachRemaining

Field Detail

map

protected final IMap<K,V> map

fetchSize

protected final int fetchSize

partitionId

protected final int partitionId

query

protected final Query query

lastTableIndex

protected int lastTableIndex

The table is segment table of hash map, which is an array that stores the actual records. This field is used to mark where the latest entry is read.

The iteration will start from highest index available to the table. It will be converted to array size on the server side.

index

protected int index

currentIndex

protected int currentIndex

segment

protected List<Data> segment

Constructor Detail

AbstractMapQueryPartitionIterator

public AbstractMapQueryPartitionIterator(IMap<K,V> map,
                                         int fetchSize,
                                         int partitionId,
                                         Predicate<K,V> predicate,
                                         Projection<Map.Entry<K,V>,R> projection)

Method Detail

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<R>

next

public R next()

Specified by:

next in interface Iterator<R>

remove

public void remove()

Specified by:

remove in interface Iterator<R>

advance

protected boolean advance()

setLastTableIndex

protected void setLastTableIndex(List<Data> segment,
                                 int lastTableIndex)

fetch

protected abstract List<Data> fetch()

getSerializationService

protected abstract SerializationService getSerializationService()